Pneumatic mounting for excavating machines



March 13, 1934. N. DE WIND PNEUMATIC MOUNTING FOR EXCAVATING MACHINESFiled July 29. 1952 Patented Mar. 13, 1934 U N 1 TE D TEES PNEUMATICMOUNTING"FOR EXCAVATING MACHINES 'NormanrDezWind; Newton, :Iowa,zassig'nor to The Parsons 00., Newton, Iowa, a corporation ApplicationJuly 29,1932, SerialNo. 625,787

3 Claims.

The object of my invention is to provide a pneumatic mounting of verysimple construction so arranged as to reduce the transmission of thestrain and shock of digging operations from the digging apparatus to themainframe of the machine to a minimum. 1

With this and other objects in view, my invention consists in theconstruction, arrangement and combination of the various parts ofmypneumatic mounting for excavating machines, whereby the objectscontemplated are attained, as hereinafter more fully set forth, pointedout in my claims, and illustrated in the accompanying drawing, in which:

Figure 1 is a side elevationof a portion of an excavating machineequipped with a pneumatic mounting embodying my invention.

Figure 2 is a detailed, sectional view taken on the line 22 of Figure 1.

'Figure3 is a vertical, detailed sectionalview taken on the line 33 ofFigure 2; and

Figure 4 is a side elevation of a slightly, difierent form of myimproved mounting.

My invention is particularly designed for use with excavating mechanismsof the kind which have a boom pivoted to the main frame of ,the machinenear one end of such frame.

On the boom is mounted an endless chain and a bucket type of excavatingmechanism. The excavating mechanism is usuallyoperated from a powerplant mounted on the main frame of the machine. The machine is mounted.on wheels or other traction devices for transportation from place toplace and ordinarily it travels under its own power.

When the boom lowered for digging a ditch, the machine travels justahead of the excavating mechanism.

The operation of the excavating mechanism in digging the dirt from theditch imposes great strain upon the main frame and other parts of themachine. The engagement of the buckets with the hard wall of the ditchtransmits severe vibration and jerking to the main frame. Many:different kinds of construction have been adopted in an attempt toreduce the transmission of this vibration and strain to a minimum, butnothing heretofore has been successful.

The result of the transmission of the vibration from the excavatingmechanism is great wear and rapid deterioration of the mechanism andparticularly of the traction mechanism including axles and such parts.

There is a tendency to cause great up and down vibration and jerking,particularly substantially inthe verticalline extending downwardly fromthe axisof the shaft on. which the boom is mounted. Thiseimposes greatshocks on the traction mechanism.

It is my objectto provide a, pneumatic device arranged substantially inthisline, whereby the transmission of shocks to the traction. membersmaybe very greatlyreduced and the jar/on the main frame and tractionmechanism may .bekept downas much-as possible.

.Inthe accompanying drawing,1 have usedthe reference numeral 10 toindicate the main frame of an excavating machine. of the type under,consideration. This frame issupportedas shown in Figures 1, 2 and 3 upontraction wheels 11 located at the rear end and carried upon the axle 12.The mount of the axle Will belater referredtolin greater detail.

The frame carries an excavating mechanism includinga boom 13 pivoted atits upperend on a shaft 14 carried by the main frame 10. Supported onthe boom is a digging mechanism of the kind having the endless chain 15.carrying the buckets or diggers. 16. This digging mechanism is operatedfrom any suitable source of power.

The boom 13 may be raised or lowered. vWhen it lowered, it inclinesdownwardly. and rear wardlyfrom the main machinev and theforward stretch.ofthe chain 15 brings. the bucket 16, into contactiwith the ground andas the excavating mechanism isoperated, the buckets cut and, carryupwardly the dirt.

.As each bucket strikes the ground, it engages it. and. causes thetransmission of a strong jerk to the main frame.

In mechanism of this kind in which the endless chain and bucketexcavating apparatus is projected downwardly and rearwardly from themain frame, there is likely to be an engagement of the buckets withstones or hard clay or the like, so that the jerking and vibrationtransmitted to the main frame is very great. It, of course, follows,that the vibrations and jerkings submitted to the traction mechanism aregreat and tend to cause wear on the axles and other parts.

I preferably locate the shaft 14 forwardly with relation to the axle 12so that the axle 12 is arranged between the lengthwise axis of the boomand a vertical line between the axis of the shaft 14 and the ground onwhich the whole machine rests.

The cushioning mechanism is then located rearwardly of this verticalline.

In Figures 1, 2 and 3, I have shown the axle 12 received in housings orthe like 17. These are pivoted or journaled as at 18 in boxings 19. Thepivot lines are lengthwise of the machine to permit the wheels to travelover obstructions and to allow for some variation in the relativeheights.

The boxings 19 are slidable in the vertical frames 20 for up and downadjustment. Above each of the frames 20 is mounted a downwardly openingcylinder 21. In each cylinder 21 travels a piston 22 connected by a rod23 with one of the boxings 19.

Connected with the upper end of each cylinder 21 is a valve structure24, such as that employed in ordinary inner tubes. Air under pressuremay be forced into the upper ends of the cylinders 21 with the equipmentat ordinary filling stations. r

The wheels 11 may be provided with pneumatic tires or may be of anykind.

In the operation of a machine of the kind heretofore described, thevibrations of the digging mechanism are transmitted to the main frameand thence to the ground. The vibrations, of course, are cushioned bythe pneumatic cylinders 21 and pistons 22 so that the complete force ofsuch vibrations is not transmitted through the main frame to the groundbut is greatly reduced and cushioned. The cushioning operation is inline between the vertical plane of the shaft 14 and the longitudinalaxis of the boom 13.

I find that where a pneumatic cushioning device of this kind is used thesaving in wear and breakage over that experienced where no pneumaticdevice is used is very noticeable.

In Figure 4, I have shown an arrangement similar to that of Figures 1 to3 inclusive except that the rear axle, which is indicated at 25, ismounted directly on the main frame without any interposed pneumaticcushion device. v

It is provided with wheels 26 having large pneumatic tires 27. The otherparts are similar to those described in connection with the structureshown in Figures 1 to 3.

The cushioning means, of course, in the secondform of my device isinterposed between the axle and the ground instead of between the axleand the main frame.

I find that where the structure here under consideration is employed,the whole excavating mechanism can be transmitted much more rapidly fromplace to place than where endless train traction devices are used, andthis is another advantage of using pneumatic cushioning members of thekind under consideration. They make it possible to employ ordinarywheels without the danger of excessive strain and breakage.

Changes may be made in the construction and arrangement of the parts ofmy improved excavating machine and it is my intention to cover by myclaims, any modified forms of structure or use of mechanicalequivalents, which may be reasonably included within their scope.

I claim as my invention:

1. In an excavating machine having a main frame and a boom pivotedthereto near the rear end of the main frame and having endless chain andbucket mechanism carried by the boom adapted to be inclined downwardlyand rearwardly from the main frame when in digging position, atransverse axle supported on the main frame, a pneumatic-tired tractionwheel on said axle, and pneumatic cushioning means for cushioning thevibrations caused by the intermittent engagement of the digging elementsof the machine with the ground, the axle, cushioning means and boompivot being substantially in a vertical plane.

2. In an excavating machine having a main frame and a boom pivotedthereto near the rear end of the main frame and having endless chain andbucket mechanism carried by the boom adapted to be inclined downwardlyand rearwardly from the main frame when in digging position, an axlesupported on the main frame, a traction wheel on said axle, andpneumatic cushioning means for cushioning the vibrations caused by theintermittent engagement of the digging elements of the machine with theground arranged substantially in but slightly rearwardly of the verticalplane through the pivotal connection of the boom with the main frame.

3. In an excavating machine having a main frame and a boom pivotedthereto near the rear end of the main frame and having endless chain andbucket mechanism carried by the boom adapted to be inclined downwardlyand rearwardly from the main frame when in digging position, atransverse axle supported on the main frame adapted for use with,pneumatic-tired traction wheels, and pneumatic cushioning means forcushioning the vibrations caused by the intermittent engagement of thedigging elements of the machine with the ground, the axle and cushioningmeans being arranged substantially in but slightly rearwardly of thevertical plane through the pivotal connection of the boom with the mainframe arranged substantially below the pivotal connection of the boomwith the main frame.

NORMAN DE WIND.

